Botulism after intragastric botulinum toxin injections for weight reduction

Although—considering the risk–benefit ratio—botulinum neurotoxin A (BoNT/A) is unequivocally recommended to treat severe neurological diseases such as dystonia, this has not yet been determined for its endoscopic intragastric injection aimed at weight reduction in obesity. However, severe adverse effects of intragastric BoNT/A had not yet been reported, prompting some European countries to endorse its (off-label) use and treat patients transnationally. We here present three cases of botulism after intragastric BoNT/A injections for obesity treatment in a Turkish hospital. Patients presented with cranial nerve affection, bulbar symptoms, and descending paresis, and benefited from treatment with BoNT antitoxin and pyridostigmine. We assume that iatrogenic botulism was induced by overdosing in combination with toxin spread via the highly vascularized gastric tissue. Of note, within a few weeks, more than 80 cases of iatrogenic botulism were reported across Europe after identical intragastric BoNT/A injections. These cases demonstrate the risks of BoNT/A injections if they are not applied within the limits of evidence-based medicine. There is a need for international guidelines to define the indication and a safe dosing scheme, especially in the context of medical tourism.     

Dysphagia after botulinum toxin injections for spasmodic torticollis: clinical and radiologic findings.

We prospectively evaluated the frequency, severity, and radiologic features of swallowing abnormalities following Botox treatment of spasmodic torticollis. We performed both clinical and radiologic evaluations of swallowing before and following Botox in 18 consecutive cervical dystonia patients receiving their first Botox treatment. Before Botox, 11% of the patients had clinical symptoms of dysphagia and 22% had radiologic signs of a peristaltic abnormality. After Botox, the signs and symptoms of dysphagia in these patients did not change, but an additional 33% developed new dysphagic symptoms and 50% of the patients developed new peristaltic abnormalities by radiologic studies. Complaints of swallowing difficulty were always associated with abnormal radiologic findings. Neither the total Botox dose nor Botox into particular muscles differed between those with dysphagia and those without.     

A case report of acute polyradiculoneuritis developing after multiple injections of botulinum toxin for cervical dystonia]

A 68-year-old man receiving four times of injection of botulinum toxin type A for cervical dystonia developed acute polyradiculoneuritis 10 weeks after the final injection. He had been complaining of paresthesia in four limbs after the second injection of the treatment. On neurological examination, bilateral facial palsy, bulbar palsy, difficulty of breath, flaccid paralysis of all limbs, sensory disturbance of all modality and areflexia in all limbs, and positive Lasèque sign were noted. Albuminocytological dissociation was present in the CSF and the conduction velocity was significantly impaired in all peripheral nerves examined. After receiving two times of intravenous highdose IgG and two times of pulse therapy, his neurological deficits gradually improved. To our knowledge, this is the third case report of acute polyradiculoneuropathy developing after botulinum toxin therapy, suggesting that botulinum toxin therapy is involved in the pathogenesis in our case.     

Vestibulo-ocular abnormalities in spasmodic torticollis before and after botulinum toxin injections.

In order to establish whether vestibular abnormalities often found in spasmodic torticollis are secondary to the abnormal head posture, the vestibulo-ocular reflex (VOR) was studied in eight patients before and after correction of head posture with botulinum toxin. Eye movements were recorded in the dark during sinusoidal and velocity step rotation. Four patients showed a significantly asymmetric response, with the slow phase of the VOR more active ipsilateral to the torticollis (chin). Despite significant improvement of the head posture in all patients for up to 10 weeks following treatment, no correction of the vestibular asymmetry occurred. This suggests that the VOR abnormalities are not caused by the head posture itself. We interpret the findings as evidence of primary involvement of the vestibular system in torticollis and we postulate a widespread derangement of the sensory-motor mechanisms controlling head posture in this disease.     

Prevalence of periocular depigmentation after repeated botulinum toxin A injections in African American patients.

Botulinum toxin A (Botox), administered by subcutaneous or intramuscular injection, is the most commonly used and most successful medication for many craniocervical dystonias. Although some patients experience side effects related to the neuroparalytic action of the medication, these side effects are temporary. In 1996, permanent periocular cutaneous depigmentation was reported in three white patients after repeated Botox injections, suggesting that loss or alteration of melanin pigment might be a permanent side effect of long-term Botox injections. The authors examined and photographed 26 African American patients who were receiving periocular Botox injections for hemifacial spasm and essential blepharospasm. The authors found no evidence of periocular cutaneous depigmentation in any of these patients.     

Writer's cramp: treatment with botulinum toxin injections

Twelve patients with writer's cramp were treated with injections of botulinum toxin. The overactive muscles were identified by clinical observation of the subjects while they were writing. Repeated injections were given at 2-week intervals until the optimal response was obtained. Eleven patients reported some benefit, which was considered by seven to be significant. Eight of the 10 patients who had pain reported moderate to significant relief. Five patients had local complications, consisting of disabling weakness of target or neighbouring muscles. These preliminary results suggest that this treatment can be successfully applied to many patients with writer's cramp without performing complex electromyographic recordings while the patients are writing.     

Generalised muscular weakness after botulinum toxin injections for dystonia: a report of three cases

Three patients are reported on who developed transient generalised weakness after receiving therapeutic doses of botulinum toxin for cervical dystonia (one case) and symptomatic hemidystonia (two cases) respectively. Clinical and electrophysiological findings were in keeping with mild botulism. All patients had received previous botulinum toxin injections without side effects and one patient continued injections without recurrence of generalised weakness. The cause is most likely presynaptic inhibition due to systemic spread of the toxin. Patients with symptomatic dystonia may be more likely to have this side effect and botulinum toxin injections in these patients should be carried out cautiously.     

Dramatic changes in muscle contractile and structural properties after 2 botulinum toxin injections

Introduction: Botulinum toxin is frequently administered serially to maintain therapeutic muscle paralysis, but the effect of repeated doses on muscle function are largely unknown. This study characterized the muscle response to 2 onabotulinum toxin (BoNT) injections separated by 3 months. Methods: Animal subjects received a single toxin injection (n = 8), 2 BoNT injections separated by 3 months (n = 14), or 1 BoNT and 1 saline injection separated by 3 months (n = 8). Results: The functional effect of 2 serial injections was exponentially greater than the effect of a single injection. While both groups treated with a single BoNT injection had decreased torque in the injected leg by approximately 50% relative to contralateral legs, the double BoNT injected group had decreased torque by over 95% relative to the preinjection level. Both single and double BoNT injections produced clear signs of fiber‐type grouping. Conclusions: These experiments demonstrate a disproportionately greater effect of repeated BoNT injections. Muscle Nerve 52: 649–657, 2015     

AACPDM systematic review of the effectiveness of therapy for children with cerebral palsy after botulinum toxin A injections

The aim of this review was to assess the effectiveness of therapy interventions on improving outcomes in children with cerebral palsy (CP) who have received botulinum toxin A (BTX-A) injections to either upper or lower limb muscles. We searched: the Cochrane Central Register of Controlled Trials; the electronic databases Medline, EMBASE, CINAHL, PEDro, SCI, and SSCI; websites of professional associations; and reference lists in trial reports and other relevant articles. We used studies on the effect of therapy on motor control, functional abilities, contracture, spasticity, and/or pain as the selection criteria. Methodological quality and the strength of evidence was assessed systematically by three independent raters using American Academy for Cerebral Palsy and Developmental Medicine (AACPDM) guidelines. Twenty-four papers met the criteria for inclusion in the content analysis of evidence. Of these, only one randomized controlled trial was available, with results demonstrating that electrical stimulation postinjection did not enhance the effects of BTX-A on gait improvement (insufficient data provided to report size of effect). Remaining papers were of level II evidence (n=2), Level IV evidence (n=5), and level V evidence (n=14). We conclude that there is insufficient evidence to either support or refute the use of therapy interventions after BTX-A injections in children with CP.     

Parotid and submandibular botulinum toxin A injections for sialorrhoea in children with cerebral palsy

The aim of this study was to determine whether botulinum toxin A (BTX-A) injected into the parotid and submandibular salivary glands of children aged 6 to 16 years with cerebral palsy (CP) and relative sialorrhoea significantly decreases their drooling and improves their quality of life. Twenty children (10 males, 10 females; mean age 10y 1mo [SD 3y 8mo]; range 6y 1mo-16y 7mo) with CP, identified as having significant daily drooling (scoring at least 6 on drooling frequency/severity scales) were recruited. BTX-A (2U/kg; maximum 70U) was injected under sedation, using ultrasound guidance (1.4U/kg and 0.6U/kg divided between parotid and submandibular glands respectively). Nineteen children completed the study: 15 with spastic quadriplegia (Gross Motor Function Classification System [GMFCS] Level V); one with dystonia (GMFCS Level V); one with hemiplegia (GMFCS Level II); and two with a mixed pattern of CP (GMFCS Levels III and V). Drooling was assessed by five methods at baseline, and 4 and 12 weeks after injection. Qualitative assessment of drooling frequency and severity scores showed statistically significant reductions at 4 weeks (p<0.001) and 12 weeks (p=0.006). Qualitative assessment of quality of life scores (rated by parents and teachers separately) also significantly improved (p<0.001 and p=0.023 respectively). Quantitative assessments showed that the number of bibs/scarves changed per day was significantly reduced at 4 weeks (p<0.001). There was no side effect from the injections themselves; 89% of parents and children wished for further intrasalivary BTX-A injections in the future. We conclude that percutaneous intrasalivary BTX-A injections into the parotid and submandibular salivary glands can reduce drooling in children with CP and relative sialorrhoea, leading to an improvement in their quality of life.     

Clinical correlates of response to botulinum toxin injections.

We studied 242 patients with cervical dystonia who had adequate follow-up after botulinum toxin injections to determine which clinical variables had a predictive value in the treatment outcome. Twenty-one patients (16%) categorized as nonresponders were compared with 113 patients (47%) considered to be definite responders. On average, the nonresponders had symptoms for 14 years longer than responders. Seventy-eight of 100 patients with complications were female compared with 54% of 190 patients without complications. In addition, patients with complications weighed less than those without complications. Both findings suggest that the occurrence of complications is related to smaller mean neck muscle mass. Botulinum toxin antibodies were detected in 35.7% of the nonresponders tested and in none of the responders. This comprehensive analysis of outcome variables leads us to conclude that patients with a long duration of dystonia before their first botulinum toxin injection respond less well than those with a short duration of symptoms, that some patients lose their responsiveness because of the development of blocking antibodies, and that women are more likely to develop complications, such as dysphagia and neck weakness, than are men.     

Change in pattern of muscle activity following botulinum toxin injections for torticollis

Twenty patients with torticollis had electromyographic studies of their neck muscles performed before and after a series of local injections of botulinum toxin. The pattern of muscle activity changed after the injections, and this effect persisted even after head position had returned to baseline. Patients who did not experience any clinical benefit from the injections also demonstrated a change in the pattern of muscle activity. These results suggest that the underlying abnormality in torticollis usually involves a general motor program for head position, rather than the activity of individual neck muscles.     

Isolated high-frequency jaw tremor relieved by botulinum toxin injections.

Jaw tremor can be seen as a component of various neurological disorders such as essential tremor, Parkinson's disease, dystonia, branchial myoclonus, hereditary geniospasm, task-specific tremor, and Whipple's disease, as well as in normal situations such as shivering, and subclinical physiological jaw tremor. In most of these conditions, the jaw tremor is usually associated with tremor or other abnormal involuntary movements affecting additional body parts, and its frequency is lower than 12 Hz. Schrag and colleagues reported a patient with a high-frequency idiopathic jaw tremor, and they speculated it could be related to orthostatic tremor affecting the masseter muscles. We encountered a similar patient with intermittent rapid focal jaw tremor that was successfully treated with botulinum toxin injections to the masseters.     

Treatment of spasmodic torticollis with local injections of botulinum toxin

Summary Thirty-seven patients with spasmodic torticollis (cervical dystonia) who received repeated local injections of botulinum toxin have been followed up for a mean period of 12.3 (10–29) months, during which time 138 treatment sessions were performed. Mean doses per muscle averaged 320 mouse units (mu; range 160–1000 mu botulinum toxin A prepared by CAMR, Porton Down, UK). Eighty-six per cent of patients experienced significant improvement of posture and 84% of those with pain had relief following the first injection. Muscular patterns of recurrent torticollis were relatively constant and in most patients efficacy was maintained with subsequent injections, while 15% of all follow-up sessions failed. Only 2 of 37 patients were consistent non-responders; 22% and 10% of all sessions were complicated by transient dysphagia and weakness of neck muscles, respectively. It is concluded that local botulinum toxin injections can be a safe and efficaceous long-term treatment of spasmodic torticollis and that optimal doses should be between 200 and 400 mu/muscle.